MANILA—Tropical Depression Pilandok maintained its strength while moving west northwestward over the Philippine Sea east of extreme Northern Luzon, the state weather bureau said Tuesday.

In its 5 a.m. tropical cyclone bulletin, the Philippine Atmospheric, Geophysical and Astronomical Services Administration (PAGASA) said the center of Pilandok was estimated at 1,050 kilometers east of extreme Northern Luzon as of 4 a.m.

The tropical depression was packing maximum sustained winds of 55 kilometers per hour near the center, gustiness of up to 70 kph, and a central pressure of 1,000 hectopascals.

Pilandok was moving west northwestward at 10 kph, with strong winds extending outward up to 580 kilometers from its center.

PAGASA said no Tropical Cyclone Wind Signal (TCWS) has been raised over any part of the country.

Despite the absence of wind signals, the enhanced Southwest Monsoon is expected to bring strong to gale-force wind gusts over most of Luzon and the Visayas, as well as Zamboanga del Norte, Misamis Occidental, Lanao del Norte, Misamis Oriental, Camiguin, Dinagat Islands, Davao Occidental, and Davao Oriental through Thursday.

PAGASA also issued Gale Warning No. 1 over the northern and western seaboards of Northern Luzon due to hazardous sea conditions.

Very rough seas of up to 5 meters are forecast over the western seaboard of the Babuyan Islands and the seaboards of Ilocos Norte.

Waves of up to 4.5 meters are expected along the western seaboards of Batanes and Pangasinan, as well as the seaboards of Ilocos Sur and northern La Union.

Sea travel in these areas is considered risky for all types of vessels, and mariners were advised to remain in port or seek shelter until conditions improve.

Rough seas of up to 4 meters are expected over the remaining seaboards of Batanes and the northern seaboard of the Babuyan Islands, while waves of up to 3.5 meters may affect the seaboard of Zambales and the western seaboard of Bataan.

PAGASA also warned operators of small seacraft, including motorbancas, not to venture into the sea in affected coastal waters, especially if inexperienced or operating ill-equipped vessels.

The weather bureau said Pilandok is forecast to gradually turn east northeastward and then northward within the next 24 hours before moving generally north northwestward afterward.

The tropical depression is expected to exit the Philippine Area of Responsibility by Wednesday evening or Thursday morning and is unlikely to make landfall in the country.

PAGASA said Pilandok may intensify into a tropical storm within the next 12 hours and could maintain that strength as it moves toward southern Japan.

The agency reminded the public and local disaster officials to continue monitoring weather advisories and take necessary precautions against heavy rains, strong winds, and rough seas associated with the Southwest Monsoon.